Shock absorber



Dec. 9, 1930. J. P. BALDwxN ET AL 197845328 SHOCK ABSORBER Filed oct.20, 192e 2 sheets-sheet 1 Een, 9? E939, .5. P. BALDAN T AL 35849325SHOCK ABSORBER Filed Oct. 20, 1926 2 Sheets-Sheet 2 Patented Dec. 9,1930 UNITED As'iATiazs v''AlllKE-S PIERC BALDWIN AND CLIFFORD GAVRVEILLr OF LOS ANGELES, CALIFORNIA;

sAiD GARVER Assienon r.ro SAID'BALDwiN SHOCK Ansomsrn Application ledOctober 20, 1926. Serial No. 142,984.

The presentV invention relates'to shock absorbers and particularly toshock absorbers vof the running friction type such, for instance, asis'disclosed in the patent granted to James Pierce Baldwin December 30,1924, No. 1,521,588.

The purpose of the invention is to provide a shock absorber which willeffectually damp the oscillations of a. motor vehicle body or othervibratory object, of simple construction, thus promoting ease ofmanufacture and assembly and lessening cost, and having av number ofimproved features of construction. Among these novel features isincluded an improved adjusting device by means of which the pull orresistance to oscillation offered by the shock absorber to movements ofthe body with which it is as-v mechanism is vdisclosed which embodiestwo friction shoes instead of three, as in Patent No. 1,521,588,referred to, together with ymeans for causing them to bear with equalpressures on the cooperating friction surfaces for all adjustments ofthe absorber.

In the drawings:

Figurel is a side elevation of portion of the front end of a motorvehicle chassis showing the manner of application of the shock absorberthereto;

VFigure 2is-a plan view of the shock absorber with portion of the casingremoved to showthe operating parts;

`Figure' is a section'on line 3-3 of Fig. 1;

Figure 4 is a plan view of the core of the absorber, one of itsprincipal operating parts; f

gigure 5 is a perspective view of the same; an v Figures 6, 7 and 8 aredetails,-

The shock absorber disclosed in Patent No. 1,521,588, previouslyreferred to, is of the friction kshoe type, there being three frictionshoes and means for thrusting these shoes outwardly against an annularfriction surface upon the occurrence of relative movenient of the twoprincipal operating parts in one direction and releasing these shoesupon the occurrence of such relative movement in the opposite direction.That shock absorber is therefore, as is the present one, of the one waytype. We havey found it possible, by modifying vthe structure dis-Iclosed inthe prior patent in certain particulars. to obtain asatisfactory running friction shoclr absorber which embodies twofriction shoes instead of three, and the present invention contemplatesthefuse of two shoes `together with mechanism which insures equalizationof bearing pressures of the two v.

shoes upon the Ycylindrical friction surface at all times during theoperation of theabsoi-ber. l

The principal parts ofthe absorber are the 'base B `and the core C,these 'parts beingA coaxial and the base enclosing the core, as can beseen from Fig. 3. The base comprises essentially a plate 10 providedwith apertures 11 to permit the insertion of bolts therethrough by meansof'which it may be securely y fastened to a support such as the sideframe member of a'motor vehicle chassis, and a shell 12 the majorportion of which is substantially cylindrical but which has a neckeddown outei1 end 13. The inner end of the shell Vis threaded to anannular flange intehollow axial spindle or tubular portion 15 projectingfrom one face thereof and eX- tending through and beyond the necked downportion 13 of the shell, 'and lugs or pedestals 16 projecting from theopposite face of the disc as can be most clearly seen in Figs. 4 and 5.`These lugs orpedestals are similar in form and their inner faces are inparallel relationship and disposed at right angles to the surface oftheidis@ 14, The channel yContact respectively vvith'the'innerfacesofcui-ved`frictinsh6esi23, f23 which engage *'theinnerfcylindricalfriction facefoffthefshell.

[cylindrical Han'jdfx 'engagey n `s termed recesses formed-'in the innerfaces of the 'frictionshoes. We also prefer to form `'fair-@24 assetforth in""Patentj1,521',588.'I TheN f 'frictinshoe's 'are providedwithspacedfricwnnf1eathe'fs25',25.@ k Y One* side jor` "wing f ofi eachpedestal is cut :':gwayf tofprovileanl abutment face`26 andv'resting'against'eachsuch face is one/endof! i'of each suchspring actsagainst the re'a'r'fa'ce `of a plunger-li ke member 28 having a pointed'forward 'end` lying' inthe; an'glefbetween the mem'bers. Springs 27":continuously 'urge the l' plungermembers l28 away from 'the abutmentfaces '26 andtendto'constantly maintain vthev friction shoes in'engagement With the cylindrical friction rtace. 'To prevent 4'sidecollapse oi" 'deformation ofthe coil I snrinh's 'thev plunger'membersVare provided i w1th1stemsf29'which extend' axially throughvrthe'wspritrgrs' -bi1t""whic`h`terminatey 'short ofrv the aljutnientfaces 26. .f Beneath theV plunger 1nembers28 'but con- "w iezi'theumsimilarihatria'l," which servez to f lnnitfthe movements of the'strntsas they move in kthe direction'which results in re wedge-'likemembers 30 may'beof' anydesired rtfrialf sov that not metallic'noise'niay bez'heardl hen the. 'movingf'strntsf" suddenly reach Atheirinner ends of non-resilient movingstrnts 22, "22," theou'te'r" ends ofthese strutsbeing in t'Pr@faaav the mae-r aids'y orL the 'Straw er@correspondingly moved upwardly (Eig.L 3) f to` nthrust thefabut-ments17, .17 outwardly Ato takefup 'loosenessl ofthe Yparts ,du'e'f to wears`.The upper end of '.the adjusting vkscrew'() is provided with"anfenlai'g'efdheadf-flwith a flat-flower kface 'whihf'rests f uponacil'cularl jzplate 142gfastnedtoitheupperendsof .pedesff talsli TheVupper end fof frthe adjusting-f 95 krvscrewfillris slottda'sat43 andextendinginto 'thgisslot'ris the fi'nnerend d'afspiralspringil,hereinafter-vdsgnated ajfsecondary: spring, Y the coils y'of"'v`s`fhichare 'disposed'f-about the ad,- Y Y)Ersting screwf Larid the ontertfendoffwhich 100 exte'ndsthrdugh'a'aperture infthetatiary f 1plate'f'42;"ThisI spring. a'constantly rtends toV f rotate thel adjustfingscreiv"in' shchdirecti'on asy to" drawitheadjusting block" 1,9: upwardly 'andithrl'lst'th'abiftnents 'outwardljn but'tlie7 105 `springisffoflsuchfstrength; .and thepitbh'y of the/thredrof scre'wv'and the4angles'foflm `clination of thefinclin'ed'k faces 'bf'r the 'v'vedge 5"'Inatf'3'rial'r` and -xnay even` be formed "integral1- 'withj theabutinents'; as :shownfin Fig'.` 7;'.but

f; berisej'in` machining allddecreasethe liability,

Vis connected by a link 32 to av bracket 33 secured upon the axle 34 ofthe vehicle. Also threaded upon the extreme outer end of thls spindleAis alock nut35'the threads of which Vare'cf the opposite hand frorntheinterengaging threads of the arm 31 and spindle 1,5 .this loc-knutbeingprovided to prevent baking Ifof theffarmffronithe r`core in' theordinary?v peatin ofthe shock absorber. kA' suitable packing ring 37fills the space beytiveen,the necked down outer end of the shell.igwapdthe interiorly threaded sleeve 38 of arm31jandprevnts theentrance of dust so l:Within the casingv 'as f well as.' the/.escape oflubricant." f K n l The Wedgel block '19 -:previously referred f to nhas an"axiallythreadedbore' 39 and'extending into Atllis boreiandhaving'A threaded relation therewith isan adjusting 5serewy40cby.meansof' whichwthe wed' e block may be.

6m' time :tof time block/19 are'siich, thabthis'canohly bedone springgfNhereihatter. `Ydesignated af. primary spring, Which'iis 'indicated at45. 'Thiswpri- Y maryy spring is-'=l1elical,' its? upper ehdfbersll'upon the bottom of the bottomfof the Wedge :block 1Q as seenfin'FigB,and its lower end r'bersupon afcylindrical' abutmentiblbckfii fwhichf`has threadedVv ,engagement with fthe interiorly threaded'walloffspindle' '15. N20

- VThepr'iiay springftends"tiothrustiblock 19 upwardly:at:'all'stimesandithereore to 'up any l'oosenes's exiingf between themov- 'ingf: struts; and the abutments lande; friction125 shoes..tWhenloseness ccursgfasoevrefexplained, andthe block 19 is movedupfwtrdiy,

f theheadofvserew 41:-is-:iliftedn 'slightly @from plate 42 or7 atleast, liftedito such kan exbent tween the screw head and the plate, thescrew 4() being rotated and the block 19 adjusted to its new position.

The adjusting block 46 is also provided with a central threaded borethrough which the exteriorly threaded bolt 47 extends. This bolt servesto retain in place a cap 4S which closes the outer end of spindle 15.The lower or inner end of screw is slotted at 49 and the lower end ofthreaded abutmentblock 46 is slotted at 50, these slots being providedfor the reception of an adjusting tool such as a screw driver. Byremoving the cap 48 the adjusting block 46 becomesk accessible so thatthe tension of spring may be increased ory decreased by rotating thisblock. Likewise by the removal of the cap 4S and block 46 a tool may beinserted in the slot 49 so that the adjustingy bolt 40 may be rotatedand the bloclr 19 raised or lowered. It will be understood thaty theplate 10 of the base may be secured to a horizontal, vertical orinclined surface and that the terms raised7 and lowered are not words oflimitation, being chosen for convenience only in describing themovements of the parts. The absorber will function in any position.

In the ordinary operation of the shock absorber, engagement of thefriction shoes with the cylindrical friction surface is brought about byrotation of the arm 31 in the direction of the arrow A shown in Fig. 2-The core C, of course, rotates with the arm 31 and the friction shoesare thrust outwardly by the moving struts 22 to engage the shell orbase. Movement of the arm and core 1n the opposite direction results inrocking movement of the moving struts toward released position, in whichposition they are shown in Fig. 2, this movement continuing until thestruts contact with the stops 30. In the friction producing directionthe struts 22 may move into contact with the eXtensions 2O of theabutments or such movement may terminate short of contact with theseextensions due to the curvature of the inner ends of the struts in themanner fully set forth in Patent No. 1,521,588, previously referred to.At all events it will be seen that inasmuch as the adjusting block 19 isunconfined laterally the struts, abutments and adjusting block comprisea floating system insuring equal thrust of the struts 22 and equalfrictional engagements of the two shoes.

The primary spring 45 should exert just the proper force to take up thewear in the shock absorber and to keep the operating parts fittingsnugly. If this spring exerts too great a force the adjustment of theblock 19 will be such that the shoes may offer too great a resistance,that is, the shock absorber may be caused to work too heavily. If thisoccurs the abutment block 46 should be moved outwardly a short distanceora lighterk spring inserted. In making this ad- 'justment it maybedesirable lto lower the Wedge block 19 somewhat since this block cannotbe-lowered merely by adjusting the tension of spring 45. This iseffected by rotation of adjusting bolt y40by means of a tool inserted inslot49.A It will be apparent that the rocking or oscillatingk movementsof the moving struts 22 in therelease direction are limited,z for allpositions of the abutment 17,--to a definite angle of inclinationsinceboth the projections 20 and the stops 30 traveloutwardly as theabutments travel outwardly and the distance b (Fig, 6) vwill be no,greater than they distance a, This is a necessary and important featurein a two shoe shock absorber. Y

While one formv of shock absorber in which the Vnovel featureswhich wehave invented are embodied is disclosed it will be apparent to-thoseskilledin the artthat the design and arrangement of the componentelements yof ,our invention maybeivaried widely without departuretherefrom. ,Particularly the automatic adjusting mechanism including theprimary and secondary springs, adjusting bolt andadj Listing block maybe'modified to suit conditions. AThis vadjusting system is.

furthermore, well Vadapted to be employed in connection k,with the shockabsorber employing three or more shoes and is not limited, to use, withatwo shoe construction. Likewise, other features of invention may beembodied fin-,shock` absorbers which vary widely inappearance andfunction.v Having :thus described `the invention, what is claimed as newand desired to be secured by Letters Patent is: Y 5

1. Ay shock absorberA of themoving strut friction shoe type and having'abutments for the strutswhich may be adjusted relatively togeach other,of an abutment adjusting device comprisinga wedge member having inclinedfaces vcontacting with the abutments respectively, a primaryspringacting directly on said wedge and a secondary spring acting on thewedge'through the Vintermediary of a screw bolt which has threadedrelation with the wedgev member. Y i v v2. A shock absorber of thefriction shoe moving strut typek andwhaving abutments for the strutswhich` may be adjusted relatively tol each other, of an automaticabutment adjusting device which includes resilient means normallytending to eifect adjustment of said device, and means for automaticallylocking the adjusting device in adjusted position. l

3. The combination set forth in claim 2 in which said lastmentionedmeansincludes a rotatable threaded member, a spring constantly tending torotate the same, and a friction element normally holding the said mem--ber against rotation.

4. For use in combination with a shock absorber of the friction shoetype, a wedge member, a primary spring urging the wedge in .yarectilinear path,ia secondary spring, and

means controlled by the secondary springfo'r lockingthe wedge 1nadjustedposition. l l

g5. VIn `a shock absorber, in combination, "g relativelyrotatablemembers, one khaving an internal cylindrical friction face'and thesec"-y ondcarrying friction shoes, rockingstruts,

i andk adjustable strut seats together Witha de `'vice for automaticallyadjusting said seats 'outwardly to compensate `:for wear, said deviceincluding awedge member in engagement f from such adjusted positionyafter each such kmovement;l f y Y "f 6..v In a'shock'absorb'er, incombination, relf atively rotatable members, one having an inwith allofsaidseats and movable axially'of said relatively yj rotatable members,means Y* f constantly urging ysaid wedgeito move'in such direction asftoeffect outward adjustment of the -strut seats, and means forautomaticalliy positivelyl locking the' Wedge vagzjtinst return ternalcylindricalfriction face and the secondV carrying friction' shoes,rockin'struts, fj

and adjustable strut seats together within, device for automaticallyadjusting said seats outwardly to compensate for Wear, said de i viceAincluding 'a wedge mer'nberv in engage-yy vment with all ofsaidiseatsandmo'vable ax,-

iallyof said relatively rotatable members, a

spring constantly' actingf'on the baselg'of the wedge'andurging thesamein such direction i o asfto`eflt'ect outward adjustmenty ofthestruty seats, and means for automatically and" ositively locking the fwedgeagainst return rom adjusted position' after each such movement.

, 7, In a shock absorber, in combination, kre1- atril'vely rotatablemembers, onehaving an in terna?! cylindrical 'friction face andthesecond carrying friction shoes, rocking struts, and ,v

le 'strut seatsk together with a device i adjusta for automaticallyadjusting said seats" outwardl'V to compensate for wear, said deviceinclu ingfa Vwedge member in engagementv l with allof said seats andmovable axially of saidrelatively rotatable members, a coiledcompression spring having one" end seated aginst the baseof the wedge,an adjustable a f tlnent for the opposite end of said springWherebyitmay be maintained in compression, andy means', forautomatically and ositivelytlockino thewedge against return rom I vsuch*adjnstedposition after each such movement.` ,Y l c y vIn testimonywhereof wehereunto aix our signatures; f l i i j V)'AMESy PIERCEBALDWIN. yCLIFFORD GARVER. j

